Guerrilla marketing is a set of unconventional marketing actions used mainly by advertisers who do not have the means to use traditional marketing channels or who want to leave the traditional beaten paths of communication.
The term guerrilla highlights this unconventionality and the common choice to make several small targeted marketing actions rather than a large campaign. It can also refers to the fact that classic rules are not respected.
Guerrilla marketing practices are sometimes on the borderline of legality or marketing and advertising ethics.
Borders are obviously blurred between what can be considered a guerrilla marketing action and an original event communication action that is however relatively conventional.
There is a semantic shift with the guerilla marketing term as original or event campaigns are often abusively called guerilla marketing campaigns.
See also other examples at unconventional marketing.
An example of street marketing operation possibly considered as guerrilla marketing operation:
In the example below, it can be considered as an event communication marketing operation but not necessarily as guerrilla marketing because all permissions were probably requested:
Many examples of what in most cases may be considered as guerilla marketing examples: